Reuben's Home Inspection Blog


It's Not A Gas Line, It's A Gas Connector

Two weeks ago I wrote a blog about the most common places to find gas leaks, and I said I'd follow up with a blog about gas connectors - those short, flexible, corrugated things that are used to connect gas appliances to gas piping.  Today I'll go over the items that I look for on gas connectors while doing home inspections.  I'll cover the most common installation defects, and I'll go over the differences between new and old connectors.

Appliance Connector

Gas Connectors are not a substitute for gas piping. To start, here's a photo of a gas connector - it's that corrugated yellow thingy.  Most newer gas connectors look just like this one.  Remember, a gas connector is used to get from the gas piping tothe appliance - that's all.  Gas connectors should never be used as a substitute for gas piping.  This means that if you ever see two connectors joined together, it's an improper installation.  If you hear someone call this a flexible gas line, smack 'em upside the head and gently correct them.  It's not a gas line, it's a gas connector.

Gas Connectors should never disappear in to a concealed location.  If a gas connector disappears in to a wall, floor, ceiling, or cabinet of an appliance, it's an improper installation.  Only proper gas piping should be run through walls, floors, cabinets, etc.

Gas Connector Diagram Gas Connector Through Floor

Gas Connectors need to be sized appropriately. I stopped by my favorite orange box the other day to check out their selection of gas connectors, and they had three sizes available - low demand, moderate demand, and large demand connectors.  It's alright to go larger, but not smaller.   The size and length of the appliance connector is determined by the BTU rating of the appliance.  Most jurisdictions allow six foot connectors for ranges and clothes dryers, and three foot connectors for everything else.

Gas Connector Sizes

Old Gas Connectors should be replaced. The current standard for gas appliance connectors is ANSI Z21.24.  I tried to get a copy of those standards for this blog so I could say what what makes the newer connectors different, but it would have cost me almost $600 (get out of here!), so I did something even better.  I got my hands on a new gas connector and an old one, and I cut 'em open.  Here's what I found.

Gas Connectors Cut Open

As you can see, they're made from different materials.  The new gas connector, which complies with ASNI Z21.24, is made from stainless steel.  The old connector obviously isn't - it's made from brass.  To quickly spot the difference between the old and new connectors, you can usually just look at the outside jacket.   Old connectors will typically have a grey coating, like the one shown above left, a braided stainless steel jacket like the type shown below, or they'll obviously be made of uncoated brass like the one shown far below.

Braided Jacket Gas Connector

Newer connectors are typically coated with yellow, like the one shown at the beginning of this blog, or will be plain stainless steel, like the one pictured at the bottom of the photo below.  If the connector has a grey coating or is made from uncoated brass, it's old.

Gas Connector Comparisons

To know for sure, you can look closely at the nut, or sometimes at a ring that has been attached to the connector.  If it meets ANSI Z21.24, it will say so.

ANSI Z21.24

If a gas connector doesn't meet this standard, it should be replaced.  The older gas connectors are much more prone to leakage, making them a latent hazard.  I've never found one that leaked, but I've heard that when they leak it's a major event.  The Truth-In-Sale of Housing programs for Minneapolis, Bloomington, and several other cities require replacement of these old connectors.  You can click here for Bloomington's position on old gas connectors.

Don't reuse gas connectors. According to every manufacturer, gas connectors should never be reused.  When a gas appliance is replaced or disconnected, the connector should be replaced at the same time.   This isn't something I look for during home inspections, just a good tip.  Oh, and one other thing - don't confuse gas connectors with Corrugated Stainless Steel Tubing (CSST).  They're not the same thing, and they're never interchangeable.   I'll have a good blog about CSST next week.


Reuben Saltzman, Structure Tech Home Inspections


Comment balloon 17 commentsReuben Saltzman • March 30 2010 05:18AM


that was an interesting post....natural gas is such a dangerous fuel if not installed properly......

Posted by Barbara Todaro, "Franklin MA Homes" (RE/MAX Executive Realty ) almost 9 years ago


Great Blog. Very informatiive. Do you ever get to Buffalo? A few months ago I had to have an new connector installed due to a small gas leak in my home there. Wasn't cheap. Wish I had seen this information first. May have tried it myself. Thank you and write some more good stuff.

Posted by Linda Scofield almost 9 years ago

Gas is so crucial and installations have to be right.  This is a great post Reuben. Good info.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) almost 9 years ago

Thanks for the lesson. I'll never look at a gas connector the same way again.

Posted by William McGowan (Coldwell Banker, Westfield, NJ) almost 9 years ago

Reuben, so when you find the older style---other than the obviously brass ones----do you recommend replacement at the time of the next servicing?  Or, are you more proactive than that.  I have not found one of the old all-brass ones in years----but still see a few of the grey ones.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) almost 9 years ago

Barbara - absolutely.  Taking care of gas connectors is one of easier things to do.

Linda - yes, we definitely inspect in Buffalo.  We have one guy in our company that lives in Delano (Duane Erickson), so he ends up doing most of the work in that area.  I'll keep writing!

Jay - thanks, I remember someone asking about these on a discussion forum, and I wasn't even able to google a good photo of the old connectors to use for an example.

Bill - you used the right term!

Charles - I recommend having them replaced right away.  I'm guessing about one out of twenty clients heeds my advice, and the other nineteen probably forget.  I probably see those old brass connectors on a weekly basis.  I saw three of the connectors with the braided stainless steel jacket yesterday alone - all in the same house.  

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) almost 9 years ago


Excellent post and presentation.  Good information for all.  I especially liked your point about any gas connector, old or new, going into concealed space.  This is a situation HABITEC finds when completing Home Inspections in Nashville and Middle Tennessee, usually when the installation was completed by an amateur and the project involved a renovation or expansion.  DIY techniques like that can lead to disasters.

Thank you,

Richard Acree

Posted by Robert Dirienzo, Home Inspections - Nashville TN (HABITEC Home and Building Inspections, LLC) almost 9 years ago

Nice info.  You took some time making this post.  Thanks.

Posted by doug diller (Goal Line Inspections) almost 9 years ago

Richard - in several communities here in the Twin Cities, these old gas connectors need to be replaced when they're old - or - improperly installed through walls / floors / cabinets / etc.

Doug - the toughest part was getting my hands on the old connectors!

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) almost 9 years ago

Having gotten to know you a little through your blogs and comments, I doubt it was very tough for you to find old connectors. I'm certain you enjoyed that part of your research :) Especially cutting them open.

This is very good information, we have gas out here in CT, but most often heating is fueled by oil and appliances by electricity. I do not often see gas connectors, but will have some new and useful info.

Posted by James Quarello, Connecticut Home Inspector (JRV Home Inspection Services, LLC) almost 9 years ago

Hello Reuben,

Another great post! I always learn from reading your articles.  Thank you! 



Posted by Rita Minion (O'Brien Realty) almost 9 years ago

Nice post! Great information.

Posted by Mike Gillingham (Eastern Iowa Inspection Services LLC) almost 9 years ago

James - LOL, ok, you got me!  I really did enjoy cutting them open.  I'm always glad when I can provide info to help other inspectors.

Rita and Mike - thanks for reading!

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) almost 9 years ago

Never thought about replacing old fittings but I guess gas lines should be.

Posted by Gene Allen, Realty Consultant for Cary Real Estate (Fathom Realty) almost 9 years ago

Banides & Debeaurain produces and sells a super simple system calld "Tracpipe". Check it out !

Posted by Robert White almost 8 years ago

Oops, i forgot the link :/

<a href=""></a>

Posted by Robert white almost 8 years ago

Robert - that's CSST.  I wrote about that stuff here

Posted by Reuben Saltzman, Delivering the Unbiased Truth. (Structure Tech Home Inspections) almost 8 years ago